Don't believe everything you've heard. The experts at the GHRI are here to debunk some popular rumors — and the explanations might help save you time, money, and frustration.

Myth: Cutting your hair makes it grow faster.Reality: What you do to the ends has no effect on the roots. Hair grows about half an inch per moth; all you can do is wait it out. However, regular trims (a quarter-inch to a half-inch every eight weeks or so) will keep ends from splitting and make your tresses look fuller and more lush as they grow.

Myth: Microwave ovens cause cancer.Reality: Intact microwave ovens do not present a risk; plus, the FDA regulates how much radiation they can leak over their lifetimes. Don't confuse this with the reported risk of microwave radiation from cell phones, which may stem from how phones are used – close to the head.

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Myth: The bigger a window air conditioner; the better it will cool you down.Reality: Air conditioners work best – and conserve energy – when they run at a consistent rate. An oversize AC tends to cycle on and off frequently, because it cools the immediate area around the unit very quickly and then stop because the internal thermostat thinks it's done; when the temp creeps up, it goes on again. A unit that's the right size is less likely to overshoot.

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Myth: You should wash chicken before cooking it.Reality: Rinsing raw chicken to rid it of bacteria that could cause food-borne illness is likely to backfire: Water droplets splashing off the meat could contaminate nearby surfaces. Instead, kill bacteria via careful cooking: Use a good thermometer to ensure that your poultry reaches an internal temperature of 165 degrees Fahrenheit. And be sure to wash hands and surfaces thoroughly after handling raw meat.